Field of Invention
The present invention relates to signal conditioning, processing, analysis, and control. In particular, the present invention relates to a parallel connection method and a device for multi-channel PD (partial discharge) signals.
Description of Related Arts
In PD signal detection filed, the parallel connection for multi-channel UHF pulse waves to transmit them in one signal bus needs to implement each channel signal can be input into the signal bus without attenuation and prevent it from transmitting to the other channel at the same time.
The following plan A and plan B is generally applied to realize signal isolation and self-triggering switch in state of the art.
Plan A: Circulator. As FIG. 1 shows, signal can only transmit from interface 1 to interface 2, from interface 2 to interface 3, from interface 3 to interface 4, from interface 4 to interface 1. So signal can be unidirectional transmitted in circulator.
Disadvantage of plan A: Circulator absorbs signal energy to isolate reverse signal. So it will cause signal attenuation by 50%.
Plan B: Switching Circuit. When switching circuit is on, it lets the signal go through, conversely isolate the signal.
Disadvantage of plan B: The general switch circuit is not self-triggering.